Funds are requested to purchase a VisualSonics Vevo2100 phased array small animal ultrasound imaging system - including transducers appropriate for cardiovascular, cancer, nephrology and diabetes research. High resolution ultrasound is the preferred modality for obtaining noninvasive anatomic, functional and molecular imaging of small animals widely used in NIH funded basic research. High resolution ultrasound provides excellent spatial resolution (35 <m x 60 <m at the highest proposed frequency), excellent soft tissue contrast and very high frame rates (up to 1000 frames per second). The newly released Vevo2100 scanner provides substantially improved performance with respect to the earlier mechanically swept single element Vevo770 scanner. Thus, the new Vevo2100 provides unique performance in terms of ability to resolve fine spatial detail (i.e. anatomic imaging), image and quantify blood flow (i.e. functional imaging) and detect molecular targeted microbubbes (i.e. molecular imaging - part of the NIH Roadmap Priorities). The Vevo2100 phased array scanner provides imaging at up to 70 MHz whereas clinical phased array scanners are limited to the 15- 18MHz range. The Vevo2100 that we propose to purchase has Color Doppler for visualizing blood flow dynamics, Power Doppler for sensitive imaging and quantification of perfusion, Pulsed-Wave Doppler for quantification of blood flow velocity. The scanner also possesses tissue tracking software to enable assessment and quantification of cardiac contractile defects. The new scanner will accelerate the pace of our research by simultaneously improving the technical quality of our scans while achieving comprehensive scans of individual animals in a few minutes as opposed to approximately one hour using existing instrumentation. The improved acquisition rate will enable more meaningful resolution of 3D displacements of the mouse myocardium. The significantly improved contrast (microbubble) imaging capability of the Vevo2100 will enable vastly superior assessment of ischemic tissue. We have obtained a letter of support from the VisualSonics founder and Chief Scientific Officer Stuart Foster indicating a high level of technical collaboration that will allow us to more fully exploit the technical capabilities of this instrument. Specifically, we continue to develop new metrics for describing cardiac function and we plan to explore the relatively untouched area of microbubble behavior under ultrasound excitation at >30MHz. This collaboration may require access to minor changes in the software to suit our research and in return some of our technical contributions may be later exploited on the VisualSonics platform so as to more widely positive impact the mouse imaging community. Eight University of Virginia-based Major Users will share access to the instrument. An additional six Minor Users will share remaining time. These users have funding from the following NIH component institutes: NIBIB, NHLBI, NCI, NIDDK, NIAID. PUBLIC HEALTH RELEVANCE: University of Virginia researchers request funds to purchase a VisualSonics Vevo 2100 small animal ultrasound imaging system with transducers appropriate for cardiovascular, cancer, nephrology and diabetes research. High resolution ultrasound is the preferred method for obtaining noninvasive images of the interior of small animals widely used in various fields of research. In this way, the instrument proposed will accelerate the pace of research, reduce the cost of conducting research (displacing more expensive methods) and reduce the total usage of research animals (by replacing sacrifice-based study with time-serial study).